A little cell biology research in the old school mode for you today: throw in some changes and see what happens. Here, the researchers build a case for the accumulation of advanced glycation endproducts (AGEs) with age (and especially with metabolic syndrome or type 2 diabetes) to interfere with the operation of heat shock proteins (HSPs). These HSPs are a vital component of the recycling and repair machinery that keeps cells operating well, and appear to be the root cause of the hormesis effect, wherein a little adverse stress put upon your biology inspires it to operate more effectively. Both calorie restriction and exercise appear to produce at least some part of their benefits on health and longevity through boosting the operation of HSPs. Here, then, is evidence for AGEs to have the opposite effect: "Nonalcoholic steatohepatitis (NASH) is a feature of metabolic syndrome. Advanced glycation end-products (AGEs) are formed by the Maillard reaction, which contributes to aging and to certain pathological complications of diabetes. A recent study has suggested that glyceraldehyde-derived AGEs (Glycer-AGEs) are elevated in the sera of patients with NASH. ... Among the intracellular Glycer-AGEs that were formed, heat shock cognate 70 (Hsc70) was identified as a GA-modified protein, and its modification reduced the activity of Hsc70."